Intentional Control for Planetary Rover SRR

Intentional behavior is a basic property of intelligence, and it incorporates the cyclic operation of prediction, testing by action, sensing, perceiving and assimilating the experienced features. Intentional neurodynamic principles are applied for on-line processing of multisensory inputs and for the generation of dynamic behavior using the SRR (Sample Return Rover) platform at the indoor facility of the Planetary Robotics Laboratory, Jet Propulsion Laboratory. The studied sensory modalities include CMOS camera vision, orientation based on an internal motion unit and accelerometer signals. The control architecture employs a biologically inspired dynamic neural network operating on the principle of chaotic neural dynamics manifesting intentionality in the style of mammalian brains. Learning is based on Hebbian rules coupled with reinforcement. The central issue of this work is to study how the developed control system builds associations between the sensory modalities to achieve robust autonomous action selection. The proposed system builds such associations in a self-organized way and it is called Self-Organized Development of Autonomous Adaptive Systems (SODAS). This system operates autonomously, without the need for human intervention, which is a potentially very beneficial feature in challenging environments, such as encountered in space explorations at remote planetary environments. The experiments illustrate obstacle avoidance combined with goal-oriented navigation by the SRR robot using SODAS control principles.     

一种新颖的双陷波超宽带天线设计

针对超宽带系统易受窄带信号干扰的问题,设计了一种新颖的基于金属开口谐振环结构的双陷波平面超宽带天线。通过在天线的辐射贴片上加载U形槽和在接地板上引入寄生条带的方法实现了双陷波特性。利用仿真软件研究了U形槽和寄生条带的物理尺寸对陷波特性的影响,并对所设计的超宽带天线进行了制作和测量。仿真和测试结果表明,天线在超宽带系统3.1～10.6GHz工作频段内的电压驻波比小于2,在WiMAX和WLAN频率范围具有良好的陷波特性,有效地抑制了超宽带通信系统与窄带通信系统之间潜在的干扰。     

Compact frequency and bandwidth tunable stopband filters using split ring resonators and varactors coupled transmission line

Two highly compact tunable stopband filters using microstrip transmission lines coupled with split ring resonators (SRRs) and varactor diodes are presented. Frequency or bandwidth tuning capability of each device is demonstrated. The frequency tunable filter, realized by a single stage, shows a wide tuning range of 19.8% with a maximum bandwidth of 5% and an insertion loss of approximately 20 dB at 4 GHz. The bandwidth tunable filter, realized by double stages, shows a 10-dB bandwidth of 19–34% with a biasing voltage of 0–10 V. The implemented frequency tuning and bandwidth tuning devices show a significant area reduction of 60.1% and 53.5%, respectively, in comparison with a similar frequency or bandwidth tunable structure presented by others. Equivalent circuit models are presented. The measured S-parameters are in good agreement with simulated ones.     

图像复原与超分辨率重构基本适用条件及提高空间分辨率上限的研究

从离散—离散的成像系统出发,在理论上分析了图像复原与超分辨率重构的基本适用条件及提高图像分辨率的上限,从图像处理的角度给出了基本适用条件的量化指标,最后对理论分析结论进行了实验验证,并对实际应用中不可避免的噪声影响进了研究,实验结果与理论研究结论一致.     

污水厂二沉池运行控制中的计算方法

二沉池运行中,池体尺寸是固定的,需要根据污泥沉降情况,确定出运行需要的回流比,表面负荷等工艺参数。常用的二沉池设计计算公式是先假定污泥浓度,SVI,回流比,表面负荷等因素,计算得出池体尺寸。对设计公式进行反向推导,则可在池体尺寸已经确定的条件下,根据曝气池污泥沉降情况,确定出合理的污泥回流比和表面负荷,从而便于污水厂运行人员对二沉池进行调控。     

Compact left-handed microstrip line based on multiple layered step impedance resonators

A novel compact left-handed (LH) microstrip transmission line is presented. To establish a negative permeability and permittivity, the transmission line is loaded with step impedance resonators (SIRs) and an array of thin wires on dual-layer architecture. Compared to existing LH structures, which incorporate conventional split ring resonators (SRRs), the proposed structure is three times smaller in size whilst achieving the same performance. To illustrate the electromagnetic properties of the metamaterial, both analytical and full wave analysis were performed and utilized to determine the effective electromagnetic parameters of the proposed structures. The experimental results show that a microstrip line periodically loaded with SIR only produces a rejection of ?6?dB at a resonant frequency of 5.50?GHz. The results also indicate a pass-band response for a left-handed microstrip line (LHML) constructed from SIR and thin wire arrays at the same resonant frequency.     

Penta-notched UWB antenna with sharp frequency edge selectivity using combination of SRR,CSRR, and DGS

This work presents penta-notched UWB antenna with sharp frequency edge selectivity using combination of SRR, CSRR, and DGS to reject the WiMAX (3.30–3.60 GHz), lower WLAN (5.150–5.350 GHz), upper WLAN (5.725–5.825 GHz), downlink of X-band satellite communication (7.0–7.40 GHz), and the uplink of X-band satellite communication (8.10–8.50 GHz) frequency bands. All these frequency bands lie within the UWB frequency spectrum. The proposed antenna is suitable for portable communication applications due to its compact dimensions. It sharply notches the existing frequency bands to mitigate the interference caused by nearby wireless communication systems within UWB frequency range. The sharp notching is achieved by the combination of complementary split ring resonators (CSRR) on the radiating semi-circular patch, split ring resonators (SRR) placed at the junction of the feedline, and a pair of defected ground structures (DGS). All notched bands can be well controlled and shifted and the equivalent lumped model of the notched bands are also developed for validation. The proposed antenna simulated, and measured results show better performance over the present state-of-the-art designs. The proposed penta-notched UWB antenna possesses better reflection coefficient, VSWR, stable gain, and small foot print. The proposed antenna has a nearly omnidirectional radiation pattern in the passbands.     

Analysis,modeling and design of a CMOS Super-Regenerative Receiver for implanted medical devices under square and sinusoidal quench signals

Medical implant devices have found widespread application in recent years. The Super-Regenerative Receiver has been one preferred architecture due to its power advantage over other architectures. We present a detailed analysis of the circuits and their equivalent models to be used in system level design of a Super-Regenerative Receiver in this paper. The design procedure is also demonstrated with a receiver design example. Designs were carried out in UMC 180 nm process with a center frequency of 416 MHz for MedRadio band. Errors between the simulation results of the proposed model and actual circuits are less than 1.6% for LNA characteristics and 7% for receiver output amplitude. 10 Mbps data rate was achieved with 432 pJ/bit energy consumption over 1.8 V power supply. The study is concluded with the simulation results of the circuits and the equivalent models.     

基于裂缝谐振环周期结构的频率选择表面

介绍了一种利用裂缝谐振环构成的缝隙型频率选择表面。使用有限元法对这种频率选择表面的电波传输特性进行了全波仿真分析。同时,提出了简单的L-C等效电路模型,并结合巴比涅原理分析预测了这种频率选择表面的谐振频率。分析结果表明,频率选择表面的谐振频率由单元结构决定,受单元周期的影响较小,而且透射波具有沿垂直于裂缝方向的极化选择性。实验测量结果与理论分析吻合。     

SRR在多线阵错位排列扫描系统中的实现

为了获得尽可能高的空间分辨率的图像,超分辨率重构技术(SRR)成为了红外扫描成像的研究热点.本文以红外多线阵错位排列扫描成像系统为研究平台,通过分析SRR实现过程及待重构图像获取的方式,分析了红外多线阵错位排列扫描成像系统中SRR有效的关键.实验表明:对于固定错位量的多排传感器扫描成像系统,影响重构图像质量的主要因素是各通道所获得的待重构图像同位像素灰度不一致引入的噪声.本文提出的基于序列逐像素比较滤波法,可以大大提高重构图像质量.